Abstract
BACKGROUND AND OBJECTIVE: Classical mycosis fungoides (CMF), the most common form of primary cutaneous T-cell lymphoma, shows marked heterogeneity in disease progression and prognosis, while reliable molecular prognostic markers remain scarce. This study aimed to evaluate the prognostic significance of GATA-binding protein 3 (GATA3) expression in early-stage CMF. METHODS: We retrospectively analyzed 106 patients with early-stage CMF diagnosed at West China Hospital, Sichuan University, between 2009 and 2021. Immunohistochemistry (IHC) was performed to assess GATA3 expression in dermal tumor cells. Associations with progression-free survival (PFS) and overall survival (OS) were examined using Cox regression models adjusted by inverse probability of treatment weighting (IPTW). Receiver operating characteristic (ROC) curve analysis was conducted to evaluate predictive performance. RESULTS: High GATA3 expression (≥ 60%) was detected in 92.5% of cases. Elevated GATA3 levels were significantly associated with reduced PFS and OS. IPTW-adjusted Cox regression confirmed high GATA3 expression as an independent adverse prognostic factor. ROC curve analysis demonstrated strong predictive performance for CMF progression (AUC = 0.867), with an optimal cutoff of 57.5% (sensitivity 73.7%, specificity 94.3%). For clinical applicability, a 60% threshold was adopted. CONCLUSION: High GATA3 expression is an independent adverse prognostic biomarker in early-stage CMF. Incorporating GATA3 into risk stratification models may improve prognostic accuracy and guide personalized treatment strategies.